Metallic chloride and method of making same



Feb. 7, 1925. 1,527,121

P. COTTRINGER ET AL 1 METALLIC CHLORIDE AND METHOD OF MAKING SAME Filed Aug. 10, 1921 ZZzz/ a $3 22 4 By h Lmm z c' zzm zs.

ATTORNEYS.

Patented Feb. 17, 1925.

UNITED STATES PATENT OFFICE.

PAUL oomrnmcnn AND WILLIAM R. commas, or MIDLAND, mcnrean, ASSIGNO-RS TO THE now CHEMICAL COMPANY, OF MmLimnmre -mAm-n CORPORATION or MICHIGAN.

-METALLIO CHLORIDE AND METHOD OF MAKING Application filed August 10, 1921. Serial No. 491,084.

To all whom it may concern:

Be "it known that we, PAUL COTTRINGl-IR and WILLIAM R. COLLINGS, citizens of the United States, and. residents of Midland,

county of Midland, State of Michigan, have jointly invented a new and useful Improvement in Metallic Chlorides and Methods of Making San1e,.of which the following is a specification, the principle of the invention being herein explained and the best mode in which we have contemplated applying that principle, so as to distinguish it from other inventions.

Calcium chloride, as well as other hygroscopic chlorides of metals of Group II, and particularly of magnesium, have been marketed for some time past in flaked condition, produced by rotating adrum maintained at a suitable temperature in contact with a .body of such chloride in fluid or molten condition, and then scraping off the layer of the material which adheres; to the surface of the drum. However, the tendency of the flaked particles, and this is particularly true in the case of calcium chloride, (0e01,), is for such particles to coalesce or adhere togetherafter being packed so as to form practically a solid body thereof again. Irrespective of the use to be made of the material, the characteristic thus referred to is obviously objectionable and has militated in no small degree against the successful employment of calcium chloride as a roadbinding material, for which it is excellently suited.

The object of the present invention, ac-

, cordingly, is to produce a metallic chloride of the class referred to above, and particularly v of calcium chloride in a flaked condition, such that it will. not harden in-the packages in time under any ordinary conditions, such hardening with the present material occurring at temperatures as low as from 115 to 135 degrees F., to which it may rise when the usual black iron drum container is exposed to the direct heat of the sun in summer.

To the accomplishment of the foregoing result, the invention, then, consists of the steps and product hereinafter fully described and particularly pointed out in the claims, the annexed drawing illustrating one typical form of apparatus adapted for the carrying out of such steps, such disclosed apparatus constituting, however, but one of the various ways in which; the the invention may be used.

In said annexed drawing The single figure there appearing trates in diagrammatic fashion an apparatus arranged for the carrying out of our improved process or method.

Ordinary flake calciumchloride contains approximately two molecules of .water of crystallization, and the present improvement consists, briefly stated, in so treating such material that the surface of each and every particle will have been dried, with the result that the material can be exposed in bulk to a temperature of from 130 to 145 degrees F or even higher, without caking.

principle of llluS- I WVhile, as indicated, the material heretofore I L marketed as flaked or granular calcium chloride contains approximatelytwo mole cules of Water of crystallization, (the average analysis-of such material being from T3 to per cent anhydrous calcium chloride), the surface of the individual particle after such special drying probably contains a great deal. more calcium chloride than the percentage range just given, and this may is carried by a chain conveyor 4 to a chute 5, through which it is dropped into an in-' ternally ffired rotary kiln 6, the temperature of the gases at the hot end of such kiln being held at approximately 400 to 47 5 degrees: C. Such kiln of course may be fired by means of an oil burner, or the products of combustion passing thercthrough may be derived from coal, coke or gas.

.The dried material as discharged from the kiln 6 will have temperature of approxi normal or average in the original material, mately 150 CI, and at this temperature a or the interlor of such particle, and as a sweating phenomenon may occur, which result the tendency of-the particles to agmay induce a tendency forthe" material to glomerate or cake cake. However, this tendency may be reduced. q v moved by running the material through a Other fgrnis may be employed embodycooling chamber 7 by means of anendlesshng' the features of' ou'r"1nvent1on instead of conveyor 8, or its equivalent,"the temperathe-on'e' here expla1ned,"change 'bemg'made ture being reduced by passage through such in the form or construction," provided the chamber to approximately 100 C.- It may elements stated by any of the following then be safely together is materially reackaged and'if the tempera claims or the equivalent of such stated eleture ranges in icatedabove have beenraQb-uments be "employed; whether produced by served, it-will ofcourse be understood that our preferred method or by others embodying steps equivalent to those stated in the following claims.

- We therefore particularly point out and served in the several steps, a product results.

In referring tothe temperatures to be obnon-caking the length of timeinvolved in each step," distinctly claim as our invention r r and particularly in the drying: step, 'is an 1. The method of treating comminuted important factor. For example, rthe -temmetallic salts containing water of crystall perature in.the,drier kilnmay berun as low zation, and normally having a hygroscopic as 110 degrees C., provided the rate at character so as to reduce their tendency to which the material is passed lthrough the cake-'in'the 'package, which consists in sukiln is properly related to the volume of air' p'erficially ydrying the particles thereof, pulled across'such material as it isbeing substantially as-described.

dried. Where a temperature as low-asthe 2. The method of treating coniminuted 1 one just indicated is employed inthe-kiln metallic salts containing water of-crystalli- I tically the same shape andsize as the'flake the sweatingphenomenon should not occur, zation to reduce their tendency to cake in .and in such case it may be unnecessary to the package, which cons sts in pass ng heatsub'sequently cool the material.

ed air over the particles thereof-while being The product resulting from ourimproved stirred so as to superficiall I dehydrate such process consists of particles retaining p'racparticles, substantially as escribed 3. In the manufacture of a metallic'chlocalcium chloride at present-omthe market, ride containing water of crystallization and but the surfaces of the individual particles, normally having a hygroscopic character,

. as previously indicated, are'given a supplethe steps which consist in preparing such mental individual driving incidentally to chloride in the form of particles, and then the passage of the material through the drying such particles to remove Water of kiln, which so changes the-character at such crystallization present in thesuperficies surfaces as to preventthe'stickigigygtogether thereof without completely dehydrating or solidifying of the materialg in -the pack-- such particles,- whereby-the tendency of such age-or when stored'iii-bulk. As-indicated particles to cake together in the packageis above our process is equally applicable to reduced.

the production of a non -cakingfiake mag 4, In the manufacture of calcium chlonesium chloride, \which still retains a porride, the steps which consist in prepa'r-in tion of the water of crystallization norsuch chloride in the form of particles, an

'mally present in such chloride} the mode of then drying such particles to remove water treatment being substantially identical as of, crystallization present in thesuperficies to the steps employed, but the temperaturesthereof without completely dehydrating in such steps requiring to be lower. Thus such particles, whereby the tendency of-the for example at the cool end of the dryer the particles to cake together in the package is temperature should not exceed 90 0., otherreduced. wise, such magnesium chloride will melt. 5. In the manufacture of a metallic'chlo- While only one specific mode of forming ride of the class described, the steps which the flake product has been described here cons st in comminut-ing the 'fusedmaterial 'n, it will be understood that our improved by cooling and mechanical meansgand then method is generally applicable to such drying the resultant particles to remove product whether made in this manner or by water of crystallization present in the sugranulating the original material in any perficies thereof without completely dehyknown way. Thus the molten chloride may drating such particles whereby the tendency be atomized, or the solid cake may be of such particles to cake together in i the crushed, and the resulting particles subpackage is reduced.

jected to a further drying operation as de 6.- In the manufacture of calcium chloscribed, wherebythe content of water in the ride, the steps which consist in comminutsurface layer of the individual particle, ing the fused material by cooling and mewhcther flake or granite, reducedbelow the chanical means, and then drying the resultant particles at atemperature of from 110 de rees C. to 47 5 degrees C.

..In the manufacture of calcium chloride, the steps which consist in bringing a cooled surface into contact with a body of such chloride in molten condition, scraping of the adherent layer or film of the chloride, whereby a flake product is formed, and then kiln-drying. such product at a temperature of from 110 C. to 47 5 C.

8. In the manufacture of calcium chloride, the steps which consist in bringing a cooled surface into contact with a body of such chloride in molten condition, scraping ofthe adherent layer or film of the chloride, whereby a flake product is. formed, then kiln-drying such product at a temperature of from 110 to 475 (1., and finally cooling such product to at-least 100 C. before packing or storing. I

9. In the manufacture of calcium chloride, the steps which consist in comminuting the fused material bycooling and mechanical means, and then drying the resultant particles to superficially dehydrate the same, such dried particles having an analysis in the aggregate of not less than 71% of .particles superficially dehydrated to the point where their tendency to cake together in the package is reduced.

' 11. As a new article of manufacture, calcium chloride containing water of crystallization, such chloride being in the. form of particles superficially dehydrated to the point where theirtendency to cake together in the package is reduced.

12. As a new article of manufacture, calcium chloride containing water of crystallization, such chloride being in the form of flake-like particles and the particles being superficially dried, whereby a portion of the water of crystallization is removed.

13. As a new article of manufacture, calcium chloride containing-Water of crystallization, such chloride being in the form of flake-like particles analyzing not less than 71 per cent of the anhydrous salt.

14. As anew article of manufacture, calcium chloride containing water of'crystallization, such chloride being in the form of flake-like particles superficially dried to the point where such particles analyze not less than 71 per cent of the anhydrous salt.

15. As a new article of manufacture a non-caking flake calcium chloride in the form of particles and having an analysis of from 71 to 75 per cent of the anhydrous salt, the particles .being surface-dried.

PAUL OOTTRINGER! WILLIAM R. COLLINGS. 

